None
Not applicable
The invention relates generally to fuel dispensing systems used to dispense gasoline for automobiles and the like and, more particularly, to an apparatus for measuring the pressure within a vapor recovery pathway in a fuel dispensing system.
Gasoline dispensing systems, including a storage tank, pump, hose and nozzle are known to the art. The nozzles found most in gasoline or service stations include a spout which is insertable into the inlet of the filler pipe of an automobile fuel tank or other storage receptacle.
As a result of various environmental regulations, many jurisdictions require that fuel dispensing systems be designed so that fuel vapors are captured and not allowed to escape into the atmosphere. Some nozzles are equipped with flexible bellows that fit over the spout and fit snugly against the opening of the filler pipe sealing the delivery of the fuel against the escape of vapors. For example, U.S. Pat. No. 4,031,930 and No. 4,016,910, assigned to the Husky Corporation, the same assignee as the present application, disclose and claim such vapor recovery systems. Other systems includes those disclosed in U.S. Pat. No. 4,429,725 to Walker; U.S. Pat. No. 4,351,375 to Polson; U.S. Pat. No. 4,232,715 to Pyle; U.S. Pat. No. 4,223,706 to McGahey; and U.S. Pat. No. 4,199,012 to Lasater.
The assignee of this application owns several patents which disclose vapor recovery systems which provide improvements over the above-listed art. For example, U.S. Pat. No. 5,197,523 provides a improved nozzle assembly by which fuel which condenses in a vapor return hose of the nozzle assembly can be extracted and returned to the fuel reservoir to help reduce atmospheric pollution. U.S. Pat. No. 5,476,125 provides a nozzle which incorporates a vapor recovery system having a fuel flow path and a vapor recovery path. U.S. Pat. No. 5,522,440 discloses a vapor recovery spout gland which is used to secure a vapor guard to the spout used with a nozzle having a body fuel flow path and a vapor recovery path.
Although the assignee""s prior nozzle designs work well for their intended purposes, it is difficult, short of absolute nozzle failure, to determine whether the vapor recovery aspect of the inventions are functioning at peak efficiency due to blockage of the vapor recovery path. It would be advantageous, therefore, to have a monitoring system that can determine system conditions during use.
It is among the invention to provide a monitoring apparatus to determine system conditions within a fuel dispensing system including a vapor recovery path.
Another object of the invention is to provide such a system that monitors vapor recovery pathway pressure during use.
It is another object of the invention is to provide such a system that monitors vapor recovery pathway pressure and transfer the information to the fuel dispenser.
Yet another object of the invention is to provide such a system that monitors vapor recovery pathway pressure and transfer the information to the fuel dispenser to control fuel dispenser functions.
Still another object of the invention is to provide such a system that monitors vapor recovery pathway pressure to transfer the information to the fuel dispenser and generate a signal to drain fuel from the vapor recovery pathway.
Another object of the invention is to provide such a system that monitors vapor recovery pathway pressure use that information to maintain proper storage tank pressure.
In accordance with the invention, generally stated, an apparatus and method for monitoring pressure within a vapor recovery pathway of a vapor recovery fuel system, The apparatus includes a pressure transducer linked to a radio frequency (RF) transponder. The transducer detects changes in vapor recovery pathway pressure and the RF transponder can relay the information to a remote site, such as the dispenser, for monitoring and control of dispenser functions. The radio frequency transponder can be housed within as spacer between the vapor recovery hose and the nozzle which can be constructed as a hose-to-nozzle break away fitting. Alternatively, the transducer can be mounted in the nozzle itself, the fuel delivery hose, or externally to any of these elements. For a balanced vapor recovery system, the invention is located between the dispensing nozzle vapor valve and the location at which vapor line return blockage is most prevalent, i.e. the lowest point in the hose. For a vacuum assist vapor recovery system, the invention can be located in the prior stated locations or inside the dispenser (gas pump) itself
The present invention allows active monitoring of pressures to detect vapor line blockage or other malfunctions. The invention then relays the detected information to the dispenser, for example, to allow monitoring of proper dispenser operation and to adjust operations parameters. The device monitors vapor recovery pathway pressure during refueling and transfer the information to the dispenser. The dispenser then utilizes the information to determine system conditions such as system failure, ORVR refueling, nozzle shutoff, and so on. The information can be utilized by the dispenser to control operations parameters, for example, vapor recovery pump speed to maintain the proper underground storage pressure or fuel drainage from the dispensing hose.